(ShareCast News) - Lonmin led the miners lower on the FTSE 250 after a downgrade from HSBC hurt the platinum producer's shares.HSBC downgraded the stock to 'hold' from 'buy' and slashed its price target to 82p from 222p. The bank said medium-term earnings and EBITDA estimates are substantially lowered by cuts in platinum group metals pricing and production expectations, and its fair value has declined by 45% from 222p to 122p.Evraz, Vedanta Resources and Kaz Minerals were also among the fallers in the mining sector.Oil and gas midcaps endured a troubling session with Tullow Oil and Premier Oil in the red, as oversupply issues and fears of a Chinese economic slowdown continued to hound the sector.On the upside, Petra Diamonds gained after reporting a 2% include in full-year production in line with the company's guidance. FinnCap reiterated its 'buy' recommendation for the stock following the report.Bwin.Party Digital Entertainment was a high riser as GVC Holdings confirmed it has raised its offer for the gaming group. Under the new terms of the offer, Bwin shareholders would be entitled to receive 122.5p for each Bwin share, consisting of up to 25p in cash and the balance of the value in new GVC shares.After revisiting their spreadsheets analysts at Exane BNP decided shares of Tate&Lyle were no longer worth 540p, but rather 525p. Nonetheless, the French broker noted the shares had fallen by approximately 20% since they were last downgraded in mid-April and the stock's relative valuation has pulled back markedly over the past quarter, they said. Hence, they opted to upgrade their view on them to 'neutral' from 'underperform'.Food producer Cranswick served up an in-line set of results at the start of the week. Underlying sales were 4% higher than in the corresponding period in 2014, while export sales to the Far East jumped 14%. Management remained confident in both the prospects for the current financial year and the continued long-term success and development of the business. FTSE 250 - RisersCLS Holdings (CLI) 1,930.00p +4.44%Wizz Air Holdings (WIZZ) 1,700.00p +3.79%Petra Diamonds Ltd.(DI) (PDL) 146.20p +3.10%Bwin.party Digital Entertainment (BPTY) 111.70p +2.85%Cranswick (CWK) 1,636.00p +2.25%Riverstone Energy Limited (RSE) 985.00p +2.18%Centamin (DI) (CEY) 55.00p +1.76%Homeserve (HSV) 435.80p +1.37%Tate & Lyle (TATE) 511.00p +1.09%Crest Nicholson Holdings (CRST) 529.00p +1.05% FTSE 250 - FallersLonmin (LMI) 54.80p -12.11%Evraz (EVR) 96.25p -7.89%Vedanta Resources (VED) 398.90p -7.73%Fidelity China Special Situations (FCSS) 137.10p -7.11%Kaz Minerals (KAZ) 158.20p -6.72%Premier Oil (PMO) 124.40p -5.90%Tullow Oil (TLW) 233.80p -5.80%Ladbrokes (LAD) 117.50p -5.32%Ophir Energy (OPHR) 106.00p -4.50%Hiscox Limited (CDI) (HSX) 891.50p -4.24%